Re:Agricultural IoT System Sends Power Through the Soil
by sidewndr46 on Monday May 06, 2024 @11:55AM
(#40276085)
interesting that you mention this. I can't find any photographs of the line. Some depictions show two wires on poles. Others show what appear to depict a pole with a single conductor wire at the top.
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Re:Agricultural IoT System Sends Power Through the Soil
by utensil4778 on Tuesday May 07, 2024 @11:27AM
(#40286894)
Yup. Short range runs could be two wires, it was more cost effective given the poor performance of the earth return system. Much longer runs were a single conductor on the pole. At either end you'd have a gigantic metal plate sunk deep into the ground to act as your return path. It had to be deep enough to stay wet, or the operator would have to dump water (or other fluid) on it.
There were also repeaters in the transcontinental run, the signal was just way too weak. These were initially electromechanical devices that dip a needle into a pool of mercury.
Things were wild before we really invented electronics.